Hydraulic valve-play compensating element for internal combustion engines

ABSTRACT

A hydraulic valve-play compensating element for internal combustion engines with two elements longitudinally displaceable relative to one another which enclose a pressure space that is separated by way of a check valve from a supply space connected to the oil circulatory system of the internal combustion engine; the supply space is thereby interconnected into the oil circulatory system to permit an oil flow through the same while means are also provided in the supply space upstream of the check valve for defoaming the oil flow.

United States Patent Ableitner et al. Oct. 21, I975 [54] HYDRAULICVALVE-PLAY 2,145,484 1/1939 Johnson 123/9056 COMPENSATING ELEMENT FOR2,153,097 4/1939 Moorhouse 123/9059 2,246,330 6/1941 Voorhies l23/90.56INTERNAL COMBUSTION ENGINES 2,250752 7/194] [75] Inventors: ErichAbleitner, Hochberg; 2,267,535 12/1941 Burkhard Stuttgart both of2,309,740 2/1943 Voorhies Germany 2,942,595 6/1960 Bergmann 123/90553,025,842 3/1962 Van Slooten 123/9058 [73] Assignee: Daimler-BenzAktiengesellschaft, 3,314,404 4/1967 Thompson 123/9035 Germany PrimaryExaminerCharles .l. Myhre [22] Flled' Sept' 1973- AssistantExaminerDaniel J. OConnor .[21] Appl. No.: 401,547 Attorney, Agent, orFirm-Craig & Antonelli [30] Foreign Application Priority Data [57]ABSTRACT Sept. 27, 1972 Germany 2247459 A hydraulic 'P Y compensatingelement for ternal combustion engines with two elements longitu- 52 usCL 23 123/9035; 123/9055; dinally displaceable relative to one anotherwhich en- 123/9056 close a pressure space that is separated by way of a[51] Int. c1. FOIL l/l8 check valve fmm Supply Space connected to theOil [58] Field of Search 123/9056, 90.57, 90.58, circulatory System Ofthe internal Combustion engine; 23 0 9055 9035, 9046, 9033 the supplyspace is thereby interconnected into the oil circulatory system topermit an oil flow through the 5 References Cited same while means arealso provided in the supply UNITED STATES PATENTS space upstream of thecheck valve for defoaming the '1 fl 2,096,257 10/1937 Moorhouse 123/905901 OW 8d 15 11/1937 Voorhies 123/9059 36 Claims, 5 Drawing Flgures US.Patent Oct. 21,1975 Sheet10f2 3,913,538

HYDRAULIC VALVE-PLAY COMPENSATING ELEMENT FOR INTERNAL COMBUSTIONENGINES The present inventionrelates to a hydraulic valveplaycompensating element for internal combustion engines, which includestwo'parts longitudinally displaceable relative to one another, whichenclose therebetween a pressure space, separated by a check valve from asupply space which is connected with the lubricating oil circulatorysystem of the internal combustion engine.

Valveplay compensating elements, in which the supply space is connecteddirectly with the lubricating oil circulatory system of the internalcombustion engine by way of a tap line, have not found acceptance todate in practice because it was not possible with tolerable expendituresto so defoam the lubricating oil foamed by the admixture of air, thatonly air-free oil reaches the pressure space. Tests to achieve a removalof air bubbles by a connection of the pressure space with the supplyspace by way of leakage oil bores or by a connection of the pressurespace with temporarily free and throttled leakage oil bores leading outof the element, did not lead to a success when these arrangements wereprovided in elements for fast-running internal combustion engines.

The present invention is therefore concerned with the task to soconstruct a hydraulic valve-play compen' sating element with directconnection to the lubricating oil circulatory system that also at highrotational speeds of the internal combustion engine, a good defoamingwith rapid removal of the air components takes place.

The underlying problems are solved according to the present inventioninthat the supply space is in communication in through-flow relation withthe lubricating oil circulatory system and in that means are provided inthe supply space upstream of the check valve which defoam the oil flow.

A safe defoaming with reliable removal of the separated-out aircomponents can be realized by the present invention, which is notinfluenced by high rotational speeds of the internal combustion engineso that the valve actuation can operate clearance-free also in thisrotational speed range with the requisite hydraulic hardness in thevalve-play compensating element.

In one advantageous embodiment of the subject matter of the presentinvention, the means for defoaming may be arranged in a structurally andfunctionally favorable manner within a separate space which is incommunication both with the inlet of the check valve as also with thesupply space and is arranged within the supply space separatedtherefrom.

This separate space may be connected with the sup ply space by one orseveral bores at a location which is disposed with the installed elementat or in proximity to the upper end of the separate space.

The means for defoaming may consist in a simple manner of a helix havinga slight pitch which slows down the oil stream.

However, the means for defoaming may also be constructed as labyrinthand finally they may also consist of a filter.

Accordingly, it is an object of the present invention toprovide ahydraulic valve play compensating element for internal combustionengines which avoids by simple means the aforementioned shortcomings anddrawbacks encountered in the prior art. I

Another object of the present invention resides in a hydraulic valveplay compensating element for internal combustion engines which is veryreliable in operation, yet involves readily acceptable expenditures forthe defoaming of the air.

A further object of the present invention resides in a hydraulic valveplay compensating element for internal combustion engines which assuresa reliable defoaming of the lubricating air by extremely simple means aswell as a reliable removal of the air bubbles under all operatingconditions.

Still a further object of the present invention resides in a hydraulicvalve play compensating element for internal combustion engines which iscapable of operating also at high rotational speeds without jeopardizingthe defoaming of the lubricating oil.

These and other objects, features, and advantages of the presentinvention will become more apparent from the following description whentaken in connection with the accompanying drawings which shows, forpurposes of illustration only, several embodiments in accordance withthe present invention, and wherein:

FIG. 1 is a partial cross-sectional view through a valve actuatingmechanism for an internal combustion engine equipped with a valve-playcompensating element having a helix for defoaming the oil in accordancewith the present invention;

FIGS. 2 and 3 are partial cross-sectional views illustrating modifiedembodiments of a valve-play compen sating element equipped with alabyrinth for defoaming the oil in accordance with the presentinvention; and

FIGS. 4 and 5 are partial cross-sectional views through valve-playcompensating elements with filters for defoaming the lubricating oil inaccordance with the present invention. 7

Referring now to the drawing wherein like reference numerals are usedthroughout the various views to designate like parts, and moreparticularly to FIG. 1, the valve actuating mechanism for an i ntemalcombustion engine includes a cam shaft 1, a rocker arm 2, a valve 3, ofwhich only the valve stem is shown, and a hydraulic valve-playcompensating element generally designated by reference numeral4. Thevalve-play compensating element 4 is arranged in a bore 5 of thecylinder head 6 of the internal combustion engine and includes two parts7 and 8. The part 7 is constructed cylinderlike and is fixedly arrangedat the cylinder head 6 by conventional means. The part 8 is constructedpistonlike and is longitudinallydisplaceably supported in the part 7.The upper end of the valve-play compensating part 8 serves as bearingsupport 9 for the rocker arm 2. The two parts 7 and 8 enclosetherebetween a pressure space 10 which is connected by way of a checkvalve 1 l with a supply space 12 disposed below the part 7. The supplyspace 12 is in communication in throughflow relationship with thelubricating oil circulatory system of the internal combustion engine inthat it is connected, on the one hand, by way of a bore 13 with a mainoil channel supplying lubricating oil and by way of a channel 14 andbores 15 and 16 with the bearing 9 to be lubricated. In other words, theconnection according to the present invention is so realized thatlubricating oil flows through the space 12 in the course of its flowpath from bore 13 into bores 15 and 16 by way of channel 14. Anessentially cylindrical member According to FIG. 4, a in the member 17whereas according to FIG. 5, also a paper filter 28 can be used for thesame purpose.

17 connected with the part 7 forms on the inside of the supply space 12a separate space 18 disposed upstream of the inlet of the check valve11; a helix 19 with slight the space 18 is sucked by the lubricating oilstreaminto' the supply space 12 through the bores 20 and together withthe lubricating oil stream reaches the bearing 9 by way of the channel14 and by way of the bores and 16, where the air is able to leave thebearing 9 by way of the bore 22. Lubricating oil discharged out of thebore 22 serves for the lubrication of the other parts of ;the valveactuating mechanism, such'as the contact sur- -v-f ace of the cam shaft1 on the rocker am 2. I

I .As t'o'the rest, theoperation of the valve-play com- :pensatingelement is conventional so that a further de- ,tailed descriptionthereofis dispensed with herein.

A labyrinth 23 may also be arranged in the member 17, as shown in FIG.2, in lieu of a helix, whereby the lubricatingoil has to flow throughthe labyrinth 23 in the axial direction. As FIG. 2 further illustrates,in lieu of bores (FIG. 1), bores 24 and 25 disposed one behind the otherin the axial direction may be provided,

'of which the bores 24 serve for the supply of lubricating oil and thebores 25 for the discharge of separated-out air.

FIG. 3 illustrates a labyrinth 26in the member 17 of the mechanism whichconsists of annular disks disposed one above the other with respectivelyoffset passage bores. I l

steel-wool filter 27 is arranged While we have shown and describedseveral embodiments in accordance with the present invention, it isunderstood that the same is not limited thereto but is susceptible ofnumerous changes and modifications as known to those skilled in the art,and we therefore do not wish to be limited to the details shown anddescribed herein but intend to cover all such changes and modificationsas are encompassed by the scope of the ment includes two memberslongitudinally displaceable relative toone another, which membersenclose therebetween a pressure space separated by a check valve meansfrom a supply space, characterized in that a lubricating oil circulatorysystem is provided, the supply space is operatively connected with thelubricating oil circulatory system, a separate oil receiving spacecommunicating with said check valve means is provided in said supplyspace, bore means are provided for communicating said supply space withsaid separate oil receiving space, and in that a defoaming means isarranged in said separate oil receiving space for defoaming the oilflowing into said pressure space.

2. A hydraulic valve play compensating element according to claim 1,characterized in that the supply space is in communication with thelubricating oil circulatory system in such a manner that a flow of thelubricating oil takes place through the supply space in the 4 course ofthe lubrication of other parts of an internal combustion engine. I

3. A hydraulic valve play compensating element accordingto claim 2,characterized inthat said parts are cal member disposed in said supplyspace, said defoaming means including a labyrinth means arranged in saidcylindrical member whereby the oil flow in said cylindrical member issubstantially in the axi thereof.

6. A hydraulic valve play compensating element according to claim 5,characterized in that a further bore means is provided for dischargingseparated air'from said separate oil receiving space.

al direction a V 7. A hydraulic valve play compensating elementaccording to claim 1, characterized in that said separate oil receivingspace is defined by a substantially cylindrical member disposed in saidsupply space, said defoaming means including a labyrinth means arrangedin said cylindrical member, said labyrinth means comprising at least twoannular disc members disposed one above the other in said cylindricalmember having offset passage bores to direct the flow from said supplyspace to said check valve means.

8.. A hydraulic valve play compensating element according to claim 7,characterized in that 'a further bore means is provided for dischargingseparated air from said separate oil receiving space. i

' 9. Ahydraulic valve play compensating element according to claim 7,characterized in that two annular discs are provided having offsetpassage bores, and in that a filter element is disposed between said twoannular discs.

10. A hydraulic valve play compensating element according to claim 9,characterized in that a further bore means is provided for dischargingseparated air from said separate oil receiving space. i

11. A hydraulic valve play compensating element according to claim 10,characterized in that said filter element is a steelwool filter.

12. A hydraulic valve play compensating element according to claim 1,characterized-in that said separate oil receiving space is defined by asubstantially cylindrical member disposed in said supply space, saiddefoaming means including an annular disc element arranged in saidcylindrical member, said disc element including a peripheral edgeportion spaced from an internal wall of said cylindrical member todefine a passage means, and in that a filter element is disposed insaid'passage means.

13. A hydraulic valve play compensating element according to claim 12,characterized in that a further bore means is provided for dischargingseparated air from said separate oil receiving space.

14. A hydraulic valve play compensating element ac- A cording to claim13, characterized in that said filter element is a paper filter.

15. A hydraulic valve play compensating element for internal combustionengines, which element includes two members longitudinally displaceablerelative to one another, which members enclose therebetween a eral boremeans. i

space upstream of the check valve means for defoaming the oil flow, thedefoamingmeans are arranged in a separate space which is incommunication both with the inlet of the check valve means as also withthe supply space, said separate space is arranged within the supplyspace, though separated therefrom, and in that the separate. space isconnected with the supply space by at least one bore means at a locationwhich is disposed at least in proximity to the upperend of the separatespace.

' 16. A hydraulic valve play compensating element according to claim 6,characterized in that said separate space is connected with the supplyspace by way of sev- 17. A hydraulic valve play compensating elementaccording to claim 6, characterized in that said location "'is disposedat the upper end of said separate space.

ing means includes a helix withslight pitch which slows down the oilflow.

means.

ply'space, bore means are provided for communicating said supply spacewith said separate oil receiving space, means are provided in saidseparateoil receiving space upstream of the check valve means fordefoaming the oil flow, said defoaming means including a labyrinth 24.An internal combustion engine comprising: a cylinder head means, a boreprovided in said cylinder head means, a hydraulic compensating meansincluding two members longitudinally displaceable relative to oneanother disposedin said bore, a pressure space"enclosed by said twomembers, a lubricating oil circulatory system for the internalcombustion engine, a supply space provided in said bore operativelyconnected with said lubricating oil circulatory system, a check valvemeans for separating said pressure space from said supply space, aseparate oil receiving means arranged in said supply space andcommunicating with said check valve means, bore means for communicatingsaid supply space with said separate oil receiving space, and adefoaming means arranged in said separate oil receiving space fordefoaming the oil flowing i 19. A hydraulic valve play compensatingelement according to claim 6, characterized in that the defoaming meansinclude a labyrinth means.

20. A hydraulic valve play compensating element according to claim 6,characterized in that the defoaming means include a filter means.

21. A hydraulic valve play compensating element according to claim 6,characterized in that the supply space is in communication with thelubricating oil circulatory system in such a manner that a flow oflubricating oil takes place through the supply space in the course ofthe lubrication of other parts of an internal combustion engine.

22. A hydraulic valve play compensating element for internal combustionengines, which element includes two members longitudinally displaceablerelative to one another, which members enclose therebetween a pressurespace separated by way of a check-valve means from a supply space,characterized in that a ludefoaming the oil flow, said defoaming meansincludes a helical member having a slight pitch in the flow direction ofthe oil for slowing down the oil flow from said supply space to saidcheck valve means.

23. A hydraulic valve play compensating element for internal combustionengines, which element includes two members longitudinally displaceablerelative to one another, which members enclose therebetween a pressurespace separated by way of a check valve means from a supply space,characterized in that a lubricating oil system is provided, the supplyspace is operatively connected with the lubricating oil circulatorysystem, a separate oil receiving space in communication with the checkvalve means is provided in said supinto said pressure space.

25. An internal combustion engine according to claim 24, furthercomprising a valve actuating mechanism, and wherein means are providedfor communicating said supply space with said valve actuating mechanismfor lubricating said mechanism.

26. An internal combustion engine according to claim 24, wherein saidbore means is disposed at least in proximity to the upper end of saidseparate oil receiving space.

27. An internal combustion engine according to claim 24, wherein saiddefoaming means includes a helical member arranged in said separate oilreceiving space having a slight pitch in the flow direction of the oilfor slowing down the oil flow from said supply space to said check valvemeans.

28. An internal combustion engine according to claim 24, wherein saiddefoaming means includes a labyrinth means.

29. An internal combustion engine according to claim 24, wherein saidseparate oil receiving space is defined by a substantially cylindricalmember disposed in said supply space, said defoaming means including alabyrinth means arranged in said cylindrical member whereby the oil flowin said cylindrical member is substantially in the axial directionthereof.

30. An internal combustion engine according to claim 29, wherein afurther bore means is provided for discharging separate air from saidseparate oil receiving space.

31. An internal combustion engine according to claim 24, wherein saidseparate oil receiving space is defined by a substantially cylindricalmember disposed in said supply space, said defoaming means including alabyrinth means arranged in said cylindrical member, said labyrinthmeans comprising at least two annular disc members disposed one abovethe other in said cylindrical member having offset passage bores todirect the flow from said supply space to said check valve means.

32. An internal combustion engine according to claim 31, wherein afurther bore means is provided for discharging separated air from saidseparate oil receiving space.

in said'supply space, said defoaming means including an annular discelement arranged in said cylindrical member, said disc element includinga peripheral edge portion spaced from an internal wall of saidcylindrical member to define a passage means, and a filter element 7disposed in said passage means.

36. An internal combustion engine according to claim 34, wherein afurther bore means is provided for discharging separated air from saidseparate oil receiving space.

1. A hydraulic valve play compensating element for an internalcombustion engine, the compensating element includes two memberslongitudinally displaceable relative to one another, which membersenclose therebetween a pressure space separated by a check valve meansfrom a supply space, characterized in that a lubricating oil circulatorysystem is provided, the supply space is operatively connected with thelubricating oil circulatory system, a separate oil receiving spacecommunicating with said check valve means is provided in said supplyspace, bore means are provided for communicating said supply space withsaid separate oil receiving space, and in that a defoaming means isarranged in said separate oil receiving space for defoaming the oilflowing into said pressure space.
 2. A hydraulic valve play compensatingelement according to claim 1, characterized in that the supply space isin communication with the lubricating oil circulatory system in such amanner that a flow of the lubricating oil takes place through the supplyspace in the course of the lubrication of other parts of an internalcombustion engine.
 3. A hydraulic valve play compensating elementaccording to claim 2, characterized in that said parts are parts of thevalve actuating mechanism.
 4. A hydraulic valve play compensatingelement according to claim 1, characterized in that the defoaming meansinclude a filter means.
 5. A hydraulic valve play compensating elementaccording to claim 1, characterized in that said separate oil receivingspace is defined by a substantiAlly cylindrical member disposed in saidsupply space, said defoaming means including a labyrinth means arrangedin said cylindrical member whereby the oil flow in said cylindricalmember is substantially in the axial direction thereof.
 6. A hydraulicvalve play compensating element according to claim 5, characterized inthat a further bore means is provided for discharging separated air fromsaid separate oil receiving space.
 7. A hydraulic valve playcompensating element according to claim 1, characterized in that saidseparate oil receiving space is defined by a substantially cylindricalmember disposed in said supply space, said defoaming means including alabyrinth means arranged in said cylindrical member, said labyrinthmeans comprising at least two annular disc members disposed one abovethe other in said cylindrical member having offset passage bores todirect the flow from said supply space to said check valve means.
 8. Ahydraulic valve play compensating element according to claim 7,characterized in that a further bore means is provided for dischargingseparated air from said separate oil receiving space.
 9. A hydraulicvalve play compensating element according to claim 7, characterized inthat two annular discs are provided having offset passage bores, and inthat a filter element is disposed between said two annular discs.
 10. Ahydraulic valve play compensating element according to claim 9,characterized in that a further bore means is provided for dischargingseparated air from said separate oil receiving space.
 11. A hydraulicvalve play compensating element according to claim 10, characterized inthat said filter element is a steelwool filter.
 12. A hydraulic valveplay compensating element according to claim 1, characterized in thatsaid separate oil receiving space is defined by a substantiallycylindrical member disposed in said supply space, said defoaming meansincluding an annular disc element arranged in said cylindrical member,said disc element including a peripheral edge portion spaced from aninternal wall of said cylindrical member to define a passage means, andin that a filter element is disposed in said passage means.
 13. Ahydraulic valve play compensating element according to claim 12,characterized in that a further bore means is provided for dischargingseparated air from said separate oil receiving space.
 14. A hydraulicvalve play compensating element according to claim 13, characterized inthat said filter element is a paper filter.
 15. A hydraulic valve playcompensating element for internal combustion engines, which elementincludes two members longitudinally displaceable relative to oneanother, which members enclose therebetween a pressure space separatedby way of a check valve means from a supply space, characterized in thata lubricating oil circulatory system is provided, the supply space isoperatively connected with the lubricating oil circulatory system, meansare provided in the supply space upstream of the check valve means fordefoaming the oil flow, the defoaming means are arranged in a separatespace which is in communication both with the inlet of the check valvemeans as also with the supply space, said separate space is arrangedwithin the supply space, though separated therefrom, and in that theseparate space is connected with the supply space by at least one boremeans at a location which is disposed at least in proximity to the upperend of the separate space.
 16. A hydraulic valve play compensatingelement according to claim 6, characterized in that said separate spaceis connected with the supply space by way of several bore means.
 17. Ahydraulic valve play compensating element according to claim 6,characterized in that said location is disposed at the upper end of saidseparate space.
 18. A hydraulic valve play compensating elementaccording to claim 6, characterized in that said defoaming meansincludes a helix with slight pitch which slows down the oil flow.
 19. AhYdraulic valve play compensating element according to claim 6,characterized in that the defoaming means include a labyrinth means. 20.A hydraulic valve play compensating element according to claim 6,characterized in that the defoaming means include a filter means.
 21. Ahydraulic valve play compensating element according to claim 6,characterized in that the supply space is in communication with thelubricating oil circulatory system in such a manner that a flow oflubricating oil takes place through the supply space in the course ofthe lubrication of other parts of an internal combustion engine.
 22. Ahydraulic valve play compensating element for internal combustionengines, which element includes two members longitudinally displaceablerelative to one another, which members enclose therebetween a pressurespace separated by way of a check valve means from a supply space,characterized in that a lubricating oil circulatory system is provided,the supply space is operatively connected with the lubricating oilcirculatory system, a separate oil receiving space in communication withthe check valve means is provided in said supply space, bore means areprovided for communicating said supply space with said separate oilreceiving space, means are provided in said separate oil receiving spaceupstream of the check valve means for defoaming the oil flow, saiddefoaming means includes a helical member having a slight pitch in theflow direction of the oil for slowing down the oil flow from said supplyspace to said check valve means.
 23. A hydraulic valve play compensatingelement for internal combustion engines, which element includes twomembers longitudinally displaceable relative to one another, whichmembers enclose therebetween a pressure space separated by way of acheck valve means from a supply space, characterized in that alubricating oil system is provided, the supply space is operativelyconnected with the lubricating oil circulatory system, a separate oilreceiving space in communication with the check valve means is providedin said supply space, bore means are provided for communicating saidsupply space with said separate oil receiving space, means are providedin said separate oil receiving space upstream of the check valve meansfor defoaming the oil flow, said defoaming means including a labyrinthmeans.
 24. An internal combustion engine comprising: a cylinder headmeans, a bore provided in said cylinder head means, a hydrauliccompensating means including two members longitudinally displaceablerelative to one another disposed in said bore, a pressure space enclosedby said two members, a lubricating oil circulatory system for theinternal combustion engine, a supply space provided in said boreoperatively connected with said lubricating oil circulatory system, acheck valve means for separating said pressure space from said supplyspace, a separate oil receiving means arranged in said supply space andcommunicating with said check valve means, bore means for communicatingsaid supply space with said separate oil receiving space, and adefoaming means arranged in said separate oil receiving space fordefoaming the oil flowing into said pressure space.
 25. An internalcombustion engine according to claim 24, further comprising a valveactuating mechanism, and wherein means are provided for communicatingsaid supply space with said valve actuating mechanism for lubricatingsaid mechanism.
 26. An internal combustion engine according to claim 24,wherein said bore means is disposed at least in proximity to the upperend of said separate oil receiving space.
 27. An internal combustionengine according to claim 24, wherein said defoaming means includes ahelical member arranged in said separate oil receiving space having aslight pitch in the flow direction of the oil for slowing down the oilflow from said supply space to said check valve means.
 28. An internalcombustion engine according to claim 24, wherein said defoaming meaNsincludes a labyrinth means.
 29. An internal combustion engine accordingto claim 24, wherein said separate oil receiving space is defined by asubstantially cylindrical member disposed in said supply space, saiddefoaming means including a labyrinth means arranged in said cylindricalmember whereby the oil flow in said cylindrical member is substantiallyin the axial direction thereof.
 30. An internal combustion engineaccording to claim 29, wherein a further bore means is provided fordischarging separate air from said separate oil receiving space.
 31. Aninternal combustion engine according to claim 24, wherein said separateoil receiving space is defined by a substantially cylindrical memberdisposed in said supply space, said defoaming means including alabyrinth means arranged in said cylindrical member, said labyrinthmeans comprising at least two annular disc members disposed one abovethe other in said cylindrical member having offset passage bores todirect the flow from said supply space to said check valve means.
 32. Aninternal combustion engine according to claim 31, wherein a further boremeans is provided for discharging separated air from said separate oilreceiving space.
 33. An internal combustion engine according to claim31, wherein two annular discs are provided having offset passage bores,and wherein a filter element is disposed between said two annular discs.34. An internal combustion engine according to claim 33, wherein afurther bore means is provided for discharging separated air from saidseparate oil receiving space.
 35. An internal combustion engineaccording to claim 24, wherein said separate oil receiving space isdefined by a substantially cylindrical member disposed in said supplyspace, said defoaming means including an annular disc element arrangedin said cylindrical member, said disc element including a peripheraledge portion spaced from an internal wall of said cylindrical member todefine a passage means, and a filter element disposed in said passagemeans.
 36. An internal combustion engine according to claim 34, whereina further bore means is provided for discharging separated air from saidseparate oil receiving space.